Loads of great ideas for you on this thread.
You need looking forward to factors, some little ones like afternoon tea with a friend or DD, bigger ones like weekend away with DH or day at the sea with the family.
Make life at home easier, allocate more jobs and reduce your workload at home, use non iron shirts ( I only iron shirts and bed linen). Buy disposable tinfoil trays to cook roast chicken, lasagne & roast dinners and throw them away, go to cash & carry and buy individual bottles/ cartons for drinks, get one of the DC s to do the shopping on line. No more pack lunches let hem make their own or buy lunch.
Declutter, declutter, declutter, make them tidy their own rooms on Saturday morning. Just clearing your drawers and cupboards out will make you feel better. Getting a cleaner will just be a source of stress utill you feel you have restored order in your home. Order a skip if necessary and get hem to help. Stop buying things or introduce one in two out for new purchases.
Get out the house and get some fresh air, you will feel better and think about rehoming the dog, you might love him but dogs are a no no in small houses, more house work, smells and chaos.
Lastly, address the selfish husband problem.